Sea salt is contaminated with micro plastics, study finds

An analysis of 16 brands of sea salt originating from eight different countries found all but one contained traces of micro plastics

Microplastic fibre inside sea pen polyp.

Michelle Taylor/Nature

Aquatic toxicologist Ali Karami and his team from the Universiti Putra Malaysia studied 16 brands of sea salt from eight different countries including Malaysia, Australia, South Africa, France, Iran, Japan, Portugal and New Zealand. Their findings were published in the journal Scientific Reports.

After dissolving and filtering the salts in their lab, the researchers found 72 particles of contaminants —most of which were identified as plastics, or pigments that may have once been plastic —in 15 of the brands. While the salt from France was not contaminated with plastic, the others contained between one to 10 particles per kilogram of salt.

Due to their low density and slow degradation, plastics are becoming the chief cross-border contaminant that often travels far from their original source. Hence, micro plastics found in the salt samples of one country could have been produced by another country thousands of miles away.

Back in 2015, a similar study in China found micro plastics in salt purchased in supermarkets there.

The concentration of plastic in sea salt is low enough that they do not present a concern for human health at present. But if plastic pollution continues unabated, those levels may increase and potentially become detrimental to human well-being.